1. Field of the Invention
The present invention relates to a process for producing a polymer or copolymer of a haloethylene compound by a suspension polymerization in an aqueous medium. More particularly, it relates to a process for inhibiting a formation of a scale of a polymer on an inner wall of a reactor, a surface of a stirrer or other parts contacting the monomer.
2. Description of the Prior Arts
As it is well known, a polymer is adhered on an inner wall of a reactor, surfaces of equipments in the reactor such as a stirrer, a baffle plate, a thermodetector etc. in a suspension polymerization of at least one monomer of haloethylene compounds such as vinyl chloride, vinyl fluoride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, and chlorotrifluoroethylene or a mixture thereof or a mixture of the haloethylene compound and a comonomer thereof in the presence of an oil soluble catalyst and a suspending agent in an aqueous medium, whereby an yield of the polymer is reduced and a function for controlling a polymerization temperature is reduced and the product is contaminated with the adhered scale to decrease the quality of the product as the disadvantages.
In view of the use of the reactor, it takes excess time and excess labour for removing the scale to disadvantageously decrease the workability and the productivity.
The adhesion of the scale on the reactor is serious trouble for the continuous process for the polymerization. The adhesion of the scale is depending upon the substrate of the reactor. The adhesion of the scale is remarkably severe in the use of the metallic substrates whereas it is slightly reduced in the use of glass lining substrates, though the disadvantages can not be eliminated.
Various studies have been made for the inhibition of the adhesion of the scales. Each method has certain disadvantage with certain advantage, and any optimum method has not been found.